This invention relates generally to containers used by plant nurseries to grow plants for subsequent sale when matured. More particularly, the invention relates to plant containers in which individual plants are produced in corresponding containers containing a soil-like growth mixture, the container retaining root growth in its interior. Even more particularly, the invention relates to plant containers having means to improve the collection of overhead water, either from rain or overhead irrigation means, the improved collection means comprising a funnel-like member extending beyond the perimeter of the main container body to increase the exposed upper surface area, with the funnel-like member having a perimeter configured to abut with other such containers to create a continuous, large-area, capture surface to prevent overhead water from falling into the spacing gaps between containers.
Nearly all landscape shrubs and a large percentage of small trees are produced in containers configured as slightly tapered cylinders with a flat circular bottom, one or more drainage holes, an upstanding annular side wall and an open circular top. These containers are typically denoted as one gallon, three gallon, five gallon, etc., containers. Container production provides many advantages over field production, but plant growth in the containers results in constricted root growth, which means that container grown plants must be irrigated much more frequently than field grown containerless plants planted directly in the ground . To produce marketable plants with good branch and leaf spread, called canopies, the containers are typically required to be spaced apart some distancexe2x80x94sometimes a distance equal to or greater than the diameter of the container itself. Because of this spacing, a majority of the water from rain and overhead irrigation from sprinkler systems falls between the containers and is wasted if not otherwise collected and reused. In addition, the plant canopies themselves direct water outside of the container perimeter. In many nursery circumstances the plant containers may cover less than 15 percent of the available ground area, and on average only between 15 and 40 percent of the overhead water will be captured by the containers and delivered to the plant roots. In circumstances where the containers are small and canopy spread is large, as little as 5 percent of the overhead water will be captured by the containers. This means that from 60 to 95 percent of the overhead water is wasted. An average sized nursery will use between 70 and 120 acre-inches of water per year, with an acre-inch equalling approximately 27,000 gallons of water. In the Southwest Florida Water Management District, a district covering roughly one-fifth of the state of Florida, landscape nurseries cover approximately 6500 acres and are allocated approximately 35 million gallons of water each day. Because the containers are designed to drain efficiently, daily irrigation is required throughout most of the year. Using the optimum efficiency figure for water capture of 40 percent, this means that over 21 million gallons of water may be wasted each day in this one district.
Despite the inefficiency of overhead irrigation from sprinkler systems, it is currently the only economically feasible method to supply water to multiple small containers. Alternatives to overhead irrigation, such as micro-irrigation by supplying small water supply tubes to each container, wicking or capillary draw of water from reservoirs beneath the containers and direct manual watering, are excessively costly, require high maintenance and often do not produce optimum growth in landscape plants.
It is an object of this invention to provide a plant cultivation container which increases the capture of overhead water by providing a larger than normal upper surface area which directs the captured water into the growth medium within the container. It is a further object to provide such a container which is low cost, which does not require changes in systems currently used to transport or fill the container pots, and which does not require the nurseries to change their current sprinkler systems for delivering overhead irrigation. It is a further object to provide such a container either as a preformed unitary device or as a multiple component device with an adaptor used in conjunction with standard cylindrical containers. It is a further object to maximize the capture of overhead water by providing containers adapted to abut to provide a continuous capture surface even when the main bodies containing the growth medium are separated a predetermined distance for optimum plant canopy growth. It is a further object to provide such a container which when used in multiples shades the plant roots from the sun and entraps ground heat in winter.
The invention comprises in general a container having a main body portion formed by the conjunction of a bottom and an annular side wall if round and multiple side walls if polygonal in cross-section, the main body having an open top with a perimeter rim, and funnel-like water collection means. The main body is adapted to receive soil or soil-like growth medium and the roots of a plant being cultivated. Typically one or more drain holes are provided to allow drainage of excess water. Adjoined to the perimeter rim of the container main body is a funnel-like overhead water collection means which comprises a sloping surface or surfaces, an inner mating perimeter and an outer perimeter, with the surfaces sloping downwards from the outer perimeter to the inner perimeter. The outer perimeter of the collection means is greater in size than the perimeter rim of-the main body of the container. In this manner the available exposed upper surface area for capturing overhead water from rain of irrigation is significantly increased beyond the surface area of the open top of the container main body, with the extra captured water being directed down the sloping surfaces into the interior of the main body to saturate the growth mixture and provide water for the growing plant.
The outer perimeter of the water collection means is configured so as to provide mating edges on all sides which can be abutted in a continuous, contiguous manner to the mating edges of other similarly configured containers, such that when multiple containers are abutted there is formed a two-dimensional enlarged water capture surface with no space or gap between containers through which water may uselessly fall. Preferably, the outer perimeter of the collection means is configured as a square with four equal mating edges. Other polygonal configurations are also possible, such as triangular or hexagonal, as well as configurations with non-linear shapes which are capable of continuously mating on all edges to form a complete surface with no gaps.
The container of the invention may be formed as a single unit including the water collection means, or the water collection means may be a separate member attachable to a standard container. The water collection means may be formed with a circular or annular inner mating perimeter adapted to externally abut the perimeter rim of the open top of the container main body, such that the main body of the container is inserted into the water collection means. The water collection means may be formed with an annular inner mating perimeter having a depending flange adapted to fit within the perimeter rim of the open top of the main body. The water collection means and the perimeter rim of the container may be formed to mechanically adjoin to secure the water collection means onto the container. The water collection means may be formed with depending insertion members or stakes adapted to be inserted into the growth mixture to secure the water collection means onto the container. The water collection means may be provided with a slit extending from the outer perimeter to the inner perimeter, allowing the water collection means to be affixed to a container with a plant having a large canopy by separating the slit and passing the trunk of the plant through the open area. The slit may be held together by the rigidity of the material composing the water collection means, or mechanical or adhesive joining means may be employed. Structural members, such as ridges or channels, may be employed on the sloping surfaces to improve rigidity, and apertures may be provided on the upper portions of the sloping surfaces to allow for release of excess captured water. The water collection means may be formed of materials providing some flexibility or configured in a hinge-like manner, whereby a nursery worker can walk between multiple contiguous containers with segments of the water collection means flexing upward to allow for passage of the worker""s leg and foot. The water collection means may further incorporate joining members to allow the containers to be secured to the ground or to each other, such as corresponding tabs and slots, or apertures or loops to receive rods or string.